Gas gauges not working on both '63 and '67 Lincoln's...

[starfireelvis]

A friend of mine has had a 1963 Lincoln Continental for two years now, and only recently found that the gasoline gauge is not working; she had both the gas tank and the sending unit replaced after purchasing the car, which had sat dormant for about a decade and saw limited driving during the 35 years before.  The gauge worked fine for most of the two years since, until she found that she ran out of gas with a reading of about a quarter of a tank in it recently.

 

She has also purchased a 1967 Lincoln Continental convertible, and the gas gauge on it is not working as well.

 

Would these possibly be grounding issues?  Any troubleshooting tips would be appreciated...

 

Thanks,

Mike

[Beltfed]

Sorry, didn't see this post till this morning.  

The first thing one needs to do is figure out if the the gauge or sender.  Power to the gas gauge itself the first thing you check.  There is no power connection to the sender.  

The second thing is to isolate the problem to either the gauge or sender.  That is done by disconnecting the one wire going to the sender from the gauge.  This can be done either at the gauge or tank, but the gauge is better in case the sender wire is open.  With power on and the wire off, the gauge will peg one way or other.  Different manufactures and years, the gauge could swing either way.  If that works, take a jumper wire with alligator clips and go from the gas sender lug on the gauge to a good ground.  The gauge should peg in the opposite direction.  Turn power off.

If the two test above were successful then your problem is the sender is not working, the wire going to the sender is open, or you have bad ground.